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One method to clean a water jacket

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  • One method to clean a water jacket

    The pix are self explanatory. Be very careful working with lye, keep it off your skin and eyes. I bolt the adapter I made to the inlet with a copper gasket. I carefully fill the water jacket to about an inch from the top with a strong lye solution. The lye gives off lots of heat when mixed, use cold water and mix it up little by little. Let it sit in the block for a week. The head is off, obviously. After a week, put a bucket under the hose of the inlet fitting hose, and open the valve into a bucket. Neutralize the lye with a half gallon of vinegar. Now you have a bucket of water where you once had lye. This can be done with the engine in the car. Work carefully to avoid getting lye into the cylinders; it will destroy your babbitt in a heartbeat. At ACE hdwe, anyway, you can still get lye, have to ask because they keep it behind the counter. Use the other fitting which attaches to your garden hose. open the valve carefully to flush, you don't want a big rush of water. Use the bowden cable sheath in your cordless drill, (stiffer than a speedo cable) and massage that thing all over the place, especially behind #4 and between 3&4. Flush with water again. Repeat until no more rust or scale comes out. The rust/scale shown I just got from a friend's block. It is only a small fraction of what I got out, the rest managed to wash away down the driveway.

    This is tedious but you will have the cleanest water jacket in the county, and your radiator won't clog up when that crap breaks lose on a longer/hotter run. Be aware that the lye does no harm to the cast iron at all.

    Machine shops used to have a large hot tank filled with lye solution and soaked blocks in it. The EPA got a hold of all that and now all bets are off. Clean it yourself, that way you will know exactly what you have.

    flush fittings.jpglye.jpgdrill and bowden.jpgrust.jpg

  • #2
    Can I suggest using a rifle bore brush on the drill?
    You wana look waaay far up da road and plan yer route because the brakes are far more of a suggestion than a command!


    • tbirdtbird
      tbirdtbird commented
      Editing a comment
      that would work quite nicely!
      you need to be able to jab the business end of the roto-rooter down into the crud pile in the bottom.....90 years worth

    • Roadster Rich
      Roadster Rich commented
      Editing a comment
      I did a clean with Evaporust and got some good advice that you need to jack up the rear end of the car to level the block so you get good coverage right up to the top from front to back.

    • Mitch
      Mitch commented
      Editing a comment
      Rich how long did you leave it soak for?

    • Jim Mason
      Jim Mason commented
      Editing a comment
      Add the lye to the water not water to lye. Small amount of water added to lye has the possibility to create steam and splash. lye will dissolve oganic material very quickly. grease, skin, eyes....etc.

    • Beauford
      Beauford commented
      Editing a comment
      yes always add a acid to water and not vice versa.

  • #3
    I left the evaporust in the block for two days. I had a simple pvc plumbing plug on the short hose on the water inlet the I screwed out when finished and let it drain into a bucket. Only problem was it was over a month before I got the head on and filled with antifreeze so it flash rusted again.


    • Big hammer
      Big hammer commented
      Editing a comment
      When I derust small parts, after rinsing yes the parts will flash rust, what I do is after rinsing with water I dunk the parts in clean Evaporust and let the parts dry. There are many ways to keep clean rust free parts from re-rusting, before painting

  • #4
    That is brilliant. I cannot wait to see more updates.
    Last edited by howel090; 09-26-2017, 09:31 PM.


    • Mitch
      Mitch commented
      Editing a comment
      howe,, welcome to the VFF

      FYI this tech thread is also duplicated in the technical forum under cooling system information for easy reference. Certain real good informative threads are put into one single category there. Look around and you''l see what i mean. I also put a link on the bottom of those tech threads to send a person back here in case there are more responses later on!!!!!

  • #5
    Chief & I stripped 8 COATS of paint, to the METAL, on my '34 Chev 5 Window, using LYE!!! That's POWERFUL SHIT!!!!
    Bill Careful


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